Copper-lead alloy process



Patented June 6, 1933 1 UNITED STATES PATENT OFFICE FREDERICK A. KORMANN, OF GLENDALE, CALIFORNIA, ASSIGNOR 'IO INDUSTRIAL RESEARCH LABORATORIES LTD., A CORPORATION OF NEVADA COPPER-LEAD AL LOY PROCESS Ho Drawing.

This invention relates to copper-lead alloys of high lead content and has for its object an improved process for producing such alloys, whereby the metal produced is 3 of perfect homogeneity and may be repeatedly remelted without Stratification.

The value of copper-lead alloys as a bearing metal of high anti-friction qualities has been known for many years, but on account of the diflerence in physical qualities of these two metals considerable difiiculty has been encountered by the metallurgist in securing satisfactory alloys where the percentage of lead was over and since a 15 permissible lead content for average bearing unit pressures may be around 40% and in anti-friction packing glands even as high as 90%, many attempts have been made to combine these metals with the aid of varizo ous fluxing materials in order to achieve the desired end of a high lead content, but to date there is no satisfactory high lead content copper-lead alloy available on the market which can be depended upon toremain as homogeneous under the various conditions of use.

In working on the problem I have found that these metals may be made to alloy perfectly in almost any proportion by incorporating a small quantity of beryllium oxideto the melt.

In carrying out the process I ma place the desired quantitiesof the metal in a crucible together with a small quantity of beryllium oxide and cover the top with charcoal to prevent oxidation, or the copper may be melted first, the beryllium andglead added. When molten, the alloy is skimmed and poured to molds.

The quantity of beryllium oxide used may vary within considerable range, but I have found that as small 'a quantity as of 1% is effective in promotin a perfectly homogeneous combination of t e metals in almost any proportion, and which in actual practice has been remelted a half dozen times without showing a tendency to separate or stratify. As a practical matter 5th of 1% by weight of the beryllium oxide to 60 the weight of the combined metals used may Application filed June a, 1932. Serial No. 615,768.

be relied upon to produce the desired homogeneity, though several times this quantity may be used.

I have also tried metallic beryllium in place of the oxide with somewhat similar results except that the resulting alloy was objectionably hard for hearing pur oses.

While I have shown the value 0 beryllium oxide with simple copper-lead alloys it has equal value in the presence of other metals frequently introduced into copperlead bearing alloys such as nickel used to change the physical attribute of the resulting metal, the effect of nickel additions being to increase the tensile strength.

Having thus described my improved process of making a copper-lead alloy, or alloy containing copper together with a high percentage of lead, what I claim is:

1. The process of making an homogeneous copper-lead alloy of high lead content which comprises meltin the metals with the addition of a relative y small quantity. of beryl- ,lium ranging between about of 1% to about 2% by weight of the combined metals.

2. The process of making an homogeneous copper-lead alloy containing upward of 25% lead which comprises melting the metals with the addition of a quantity up to about 2% of beryllium oxide.

3. The process of making an homogeneous alloy containing copper and lead with the latter in excess of 25% which comprises melting the metals in the presenceof a relatively small quantity of beryllium oxide ranging between about its of 1% to about 2% by weight of the combined metals While avoiding oxidation of the surface of the melt.

FREDERICK A. KORMANN. 

